Mobile/portable personal communications and computing devices can use touch (touch-on-surface) technology for input. For example, touch buttons and touch sliders can be integrated into a device case. Such touch input elements/apparatus are distinguished from, for example, capacitive touch buttons defined on a device display panel. These touch input elements/apparatus are commonly located on a case edge, but also can be located on a bezel area of the display surface, or on the back of the device case.
For such touch input elements (for example, sliders or buttons), touch sensing is used for touch sensing to detect, for example, touch-press (button) or a touch-position (slider). Touch sensing can be based on capacitive/inductive sensing of physical deflection/deformation of the touch surface, or capacitive human body (finger) touch/presence. Touch sensing technologies can be used with different touch surfaces, including metal (conductive), and glass/plastic (nonconductive), which depending on the application/technology can include a conductive coating.
Touch sensing technologies can be used to detect both XY touch position on a touch surface, and touch force, such as based on the amount of surface deflection, or a change in sensed human body capacitance as finger pressure expands a touch contact area.